Of all substances blood is the most dangerous to the mhondoro. If blood falls on the ground drought follows. Blood is as it were, anti-rain. By their ability to control the rain the mhondoro, the ancestors of the lineage, demonstrate that the only kind of fertility that is worth having is in their gift.

People who are childless cannot become midzimu because, so it is argued, they have no descendents to look after or to act as mediums for them. When such a person dies she or he becomes a ngozi who wanders through the villages angry and malicious, bringing harm and destruction for no other reason than its unquenchable fury and spite.

The typical act of witchcraft is cannibalism or, more accurately, necrophagy. Witches kill people, including their own children, or rob graves to find human flesh to eat. They commit incest and adultery. They run about to do their evil deeds naked at night. They ride on the backs of hyenas. They can transform themselves into hyenas, crocodiles or snakes at will. Hyenas, crocodiles or snakes act as familiars for witches, as mayzvidoma, very small people the size of children who carry out the witches’ commands.